A mobile communication system related to the present invention will be described with reference to FIG. 19. The mobile communication system related to the present invention include terminals 903 which are movable wireless devices used by users and called UE (user equipment) in the LTE (Long Term Evolution), radio base stations 902 which communicates with the terminals 903 and are called eNB (enhanced Nodes B) in the LTE, and a core network 901 which is an upper network of these nodes and called a MME (mobility management entity) and a SGW (serving gateway) in the LTE.
In addition, as interfaces between these above nodes, there are an RRC (radio resource control) interface 913 as a radio interface, an X2 interface 912 as an interface between the base stations 902, and S1 interfaces 911 as interfaces respectively between each of the base stations 902 and the core network 901.
In the network of the mobile communication system, the utilization rate dynamically varies according to a difference in time, place, radio environment, or the like. As used herein, the utilization rate refers to the resource utilization state of the hardware in the radio base station or the core network, the wireless or wired band occupancy rate of the RRC, X2, or S1 interface, the number of users, or the amount of data.
In mobile communication system, there are technologies for reducing the utilization rate such as user acceptance control and congestion control (for example, see Patent Literature 1). On the other hand, in order to increase the profits of the operator of a mobile communication system and to increase user satisfaction, it is preferred to increase the utilization rate of the network to flat and smooth it.